Tellus

An amplification of random perturbations by the interaction of non-linearities internal to the climatic system with external, orbital forcing is found. This stochastic resonance is investigated in a highly simplified, zero-dimensional climate model. It is conceivable that this new type of resonance might play a role in explaining the lo5 year peak in the power spectra of paleoclimatic records.

This article discusses the rôle of the THC in climate, based upon the results of several numerical experiments which use a coupled ocean-atmosphere model developed at the Geophysical Fluid Dynamics Laboratory of NOAA, USA. The first part of the article explores the mechanism which is responsible for the abrupt climate change such as the Younger Dryas event using the coupled model. In response to the freshwater discharge into high north Atlantic latitudes over a period of 500 years, the THC in the Atlantic Ocean weakens, reducing surface air temperature over the northern north Atlantic Ocean, the Scandinavian Peninsula, and the circumpolar ocean and Antarctic Continent of the southern hemisphere. Upon the termination of the water discharge at the 500th year, the THC begins to intensify, regaining its original intensity in a few hundred years. In addition, the sudden onset and the termination of the discharge of freshwater induces the multidecadal fluctuation in the intensity of the THC, which generates the almost abrupt change of climate. It is noted that similar but much weaker oscillation of the THC is also evident in the control integration of the coupled model without freshwater forcing. The irregular oscillation of the THC mentioned above appears to be related to the fluctuation of the Subarctic Gyre and associated east Greenland current, yielding the evolution of the surface salinity anomaly which resembles that of ''great salinity anomaly''. The second part of this article describes the response of a coupled ocean-atmosphere model to the doubling and quadrupling of atmospheric carbon dioxide over centuries timescale. In one integration, the CO 2 concentration increases by 1%/year (compounded) until it reaches 4× the initial value at the 140th year and remains unchanged thereafter. In another integration, the CO 2 concentration also incleases at the rate of 1%/year until it reaches 2× the initial value at the 70th year and remains unchanged thereafter. One of the most notable features of the CO 2-quadrupling integration is the gradual disappearance of thermohaline circulation in most of the model oceans during the first 250-year period, leaving behind wind-driven cells. For example, thermohaline circulation nearly vanishes in the north Atlantic by the 250 years of the integration and remains very weak until the 900th year. However, it begins to restore the original intensity by the 1600th year. In the CO 2-doubling integration, the thermohaline circulation weakens by a factor of more than 2 in the North Atlantic during the first 150 years, but almost recovers its original intensity by the 500th year. The weakening of the THC moderates temporarily the greenhouse warming over the north Atlantic Ocean and its vicinity. In both numerical experiments described above, the initial weakening of the THC results from the capping of oceanic surface by relatively fresh, low-density water, which surpresses the convective cooling of water in the sinking region of the THC.

Neste artigo, tecemos considerações sobre uma manifestação da cultura e identidade do Povo Bororo a partir do diálogo com o contexto sociocultural e histórico de Meruri, em Mato Grosso. O Jure como uma prática social se expressa como educação do corpo que se materializa na dança e no brincar possibilitando a compreensão de diferentes sentidos e significados em diálogo com a cosmologia complexa deste Povo que há 300 anos se mantém com a língua e os rituais a sua complexa estrutura social e formas de constituir suas identidades individuais e coletivas. A dança se constitui numa prática polissêmica cuja expressão revela quem são os corpos que dela participam e conforme os contextos essa transcende sua especificidade ritualística ou lúdica para promover interações e processos de educações dos corpos numa perspectiva intercultural.

While recent readings of Varro’s De Re Rustica have emphasized a negative view of contemporary politics and mores across all three books, this ar- ticle identifies an oppositional contrast between Rust. 1 and 3, set in the temple of Tellus and the Villa Publica, respectively. Arguing that Varro intentionally casts the Villa Publica—and its analogue, villatica pastio—as the more success- ful integration both of Rome’s rural past and urban present, and of its elite and non-elite citizens, it suggests that Varro took a more populist view—of the Villa Publica, villatica pastio, and the governance of the res publica itself.

The location of the Temple of Tellus is still debated, and is one of the key questions in the reconstruction of the urban landscape between the Velia and the Carine. By re-eval- uating the archaeological data, epigraphs, lit- erary sources and information from ancient sources of the late-Renaissance era, the arti- cle reconstructs the history of the Tellus building and its neighborhood over the cen- turies. Drawing up maps of that period illus- trates the transformations that took place in this city quarter from the earRepublican Age to the early Imperial Age, until the late classical era, a period when the ancient place of worship assumed new significance in rela- tion to the City Prefecture.

Copyright 2020-08-31 Régis Duval,Texte déposé, communiqué à Académie des Inscriptions et Belles Lettres (Paris)-The Roman family during the Republican period : Tellus-Farreus-Ceres and the other gods that presided over potestas and dominium exercize in Roman families, from the wedding day of parents to the day of civic autonomy of their children of both genders. Synopsis.  The present paper examines how the socio-theologians (Pontiffs) of ancient Rome applied to the juridico-religious matters of families the same general concepts we have highlighted in general terms in our work ''The factory for community gods of social entities of every type and size in archaic Etrusco-Tiberine Italy''. The said model argues on a general basis that the daily activities of any social group or community was patronized religiously by precise sets of divinities, tailored around the specifics of each community as a function of their socioeconomic characteristics, in such a way as to satisfy the needs for their smooth and seamless integration within the global society they partook of, and meeting harmoniously tuned terms to requirements of the divine sphere as were collectively anticipated/fancied, thus leveraging entirely distinct social problematics while relying on one unique structural scheme. The structures highlighted by our general model ensure : a) the management of any community's ''territory'', whether geographical, economical, judiciary, social… within which the said community is legitimate to exercize its authority, under the patronage of a ternary set of male divinities gifted each with specific, separate properties that modelize and allegorize ''territory'' as a ternary object (''boundaries'', ''expanse/range/scope'', ''core'' or ''home''), the well-known so-called archaic Roman triad Quirinus/Mars/Jupiter presenting in the main the set of properties that characterize such a triad*. This territorial ''object'', over which is exercized ownership, is managed, when it reads about socio-political matters, by the notion of imperium, as we have argued in our document ''Potestas and imperium : how the Executive power roles in Republican Rome based their legitimacy on the religious archetype of the territory-control and populus-protection triads''. The present additional analysis argues that private property, whether of real estate or movable property nature, this latter including family members themselves, spouse (mater familias), children (liberi), slaves (familiares), as well as cattle, was administered in an exactly similar way through the notions of dominium and of mancipium, under the patronage of the pater familias's Lares ; it is argued in addition that manus exercized over family women evolved flexible forms developed in order to meet the specific rationales relating to the position of females within society so as to maintain a link with their original bloodline group, a return-home warranty in case of first magnitude mishaps, thanks to the capability of remancipatio, a process made over time more stringently required by the increasing numbers of insufferable conditions created by ever more commonly encountered contexts of widowry, divorce, emancipation and adoption. b) the management of the development dynamics of each separate community, which we generically designate as a ''populus'', whether this relates to actual demography (family, super-families or gentes, village, town, population of a City, population of a State, group of related people…), social groups (military : legion, navy crew(s), foot or horse troops…. ; classes of citizenry : slaves servi/ancillae, full fledged Roman citizens [quirites, ingenui], Latin citizenry, freedpeople [libertini]… ; sub-structures within the citizenry leveraging different social and political rights : Patriciate, Plebs ; or political purposes: tribes, curiae, centuries…. ; outsiders as of different classes : peregrini, hostiles), economic entities (trade corporations), and even entirely conceptual categories (''travelers'', enemies on the battle field…), under the patronage of a ternary set of one male divinity and two female divinities gifted with symbolic properties with complementary roles on behalf of the community within the frame of a collective intervention, mimicking human reproduction, the well-known so-called Capitoline triad of Rome Minerva/Jupiter Optimus Maximus/Juno presenting in the main the set of properties that characterize such a triad* 1. These development dynamics of each community, on which rests its mainstream activity, are administered, when it reads about social executive power roles, through leveraging the notion of potestas, as argued in our previously released work ''Potestas and imperium : how the Executive power roles in Republican Rome based their legitimacy on the religious archetype of the territory-control and populus-protection triads''. The present additional analysis argues that private life drivers, based on the usage done of owned property, whether of real estate or movable property nature, this latter including family members themselves, spouse (mater familias), children (liberi), slaves (familiares), as well as cattle and other goods encompassed in the scope of boni sui were administered in an exactly similar way through the notion of potestas, under the patronage of the pater familias's populus triad, the which was frequently Tellus/Farreus/Ceres involved in the couple's creation at wedding, heavy with agrarian references, although probably variable with ethnic origins, Tellus swapping roles with Vesta, Flora, Fortuna or other intermediation goddesses, Jupiter with Janus, Priapus or other male priapic gods, and Ceres with Fornax, Juno, Venus, Feronia or other fosterhood mother-goddesses. How the purely genesic dimension of the pater familias/mater familias couple was patroned by a pair of Di Magni, nor how personal life events governed by fates were patroned by a female divinity with triple facets such as Mania or by a full fledged triad of female goddesses such as Parcae, nor related notions to both set of problematics are addressed here. In the course of this analysis, we refine the view we previously developed of Tellus as a female intermediation goddess and discuss her relationship to Terra, as well as the concurrent role of Flora. We discuss the case of Ceres as patron of family matters. We discuss the case of Lares as patrons of family matters. We analyse from a religious perspective the status of women in all their life situations, celibacy-wedlock-widowhood-remarriage. We discuss the religious problematics raised by the Plebs/Patriciate intermarriage issues versus auspicia and bloodline, and how the Pontiffs solved the issue so as to preserve the identity/purity of the Patriciate despite the day-today realities of dwindling families ever more connected to an ever growing mass of affluent Plebeians. Collaterally, we also provide a new view of Bona Dea, as of Etruscan, more precisely Veian, origin, associate of Medicus, presiding to females' social status as uxores sine manu for the women of the higher Roman social classes. We propose a new view of the vindicta as originally the instrument by which peregrini of the Asylum were anointed into Roman citizenship after a probation periode ascertaining they were not claimed as slaves by some party. We argue that libertas originally qualified the situation of people that were under potestas to no one. We additionally sketch how the Roman Republic was reshaped in depth by the political and religious reforms of Furius Camillus, making him effectively the 2 nd Romulus. We also reanalyse the terms of relationship between Cato the Younger and Marcia when she moves back in his domus after Hortensius's demise. We finally propose a scenario how Venus was introduced by the Fabii within a vast Etruscan inflow into Rome and then developed inside, and we propose a systemic interpretation of Tellus in relation to the Piacenza liver and we argue her identification with Tluscv (tiur part). 1 *We highlight in another work certain limits to the qualification of these precise two triads to a claim as reference models.

ABSTRACT:  The Ara Pacis Augustae (Altar of Augustan Peace) is examined as a shrine of light consistent with the astro-orientation principles of Roman architect Vitruvius (c.25 BC).  Italian archaeologists  excavated (1937-38) and relocated the altar along Rome’s Tiber River – rotating it 75º counter-clockwise from the original orientation.  While its magnificent marble sculpture may be viewed at the Museo dell’Ara Pacis, a key astronomical component of the  altar’s architectural design has until now remained encoded on a paper site plan.  The author calculated the horizon declination (+11.3º decl.) of the altar’s original northeast opening with Program STONEHENGE (Hawkins 1983, 328-330), Guglielmo Gatti’s 1938 site map, and Google Earth satellite imagery: True Azimuth ≈ 75º; Latitude/Longitude = 41° 54’ 10.47” N/12° 28’ 44.60” E; Elevation ≈ 10 meters ASL; and Horizon Altitude ≈ +1.1º.  The Ara Pacis Augustae was dedicated in 9 BC (Moretti 1947,7).  Analysis shows that the axis of the Ara Pacis enclosure’s northeast opening originally was oriented to the rising Sun (+11.0º decl.) on both April 21st and August 27th.  However, the iconography of the Ara Pacis supports an interpretation that only the April 21st sunrise orientation was intended, because each sculpture of the “Tellus” frieze (young woman, flowing amphora, pair of fishes, ram, bull, infant twins) uniquely mirrors the astronomy: Venus (Morning Star phase) and the Zodiac constellations Aquarius-Pisces-Aries-Taurus-Gemini at dawn on the festival of Par ilia (Pales, goddess of shepherds), 21 April 9 BC.  This date coincides with the founding of Rome on 21 April 1 ab urbe condita (753 BC) as recorded by Roman historian Marcus Terentius Varro.  What could be a more fitting venue than the Museo dell’Ara Pacis for exhibiting a virtual 3D animation of the annual sacrifice connecting the Pax Augusta of the SPQR to the Cosmos of the Immortal Gods on the dawn of the Dies Natalis Romae?

ASTRATTO:  L'Ara Pacis Augustae è esaminata in base al precetto astro-architettonico di Vitruvio secondo cui <<…chi si professa architetto dovrebbe essere ben versato in …astronomia e nella teoria dei cieli>>  (De Architectura, I.i.3; IX).  Nel ricollocare l'Ara Pacis per l'esposizione delle sue magnifiche sculture marmoree nel nuovo Museo dedicato all’Ara Pacis (1937-1938), l'altare fu ruotato di 75°, cancellando così ogni allineamento astro-architettonico originario. Poiché la mappa del sito dell'archeologo Guglielmo Gatti del 1938 documenta l'orientamento originale dell'altare, l'autore è stato in grado di calcolare la declinazione (δ) del sole sull’orizzonte astronomico (+11,3ºδ) riferito all’apertura nord-est dell'altare utilizzando i programmi STONEHENGE (Hawkins 1983, 328-330) e Google Earth Pro Digital Elevation Model, con i seguenti dati:  True Azimut ≈ 75º; Latitudine/Longitudine = 41°54'10,47"N/ 12°28'44,60"E; Altitudine ≈ 10m slm; e Altezza angolare dell'orizzonte locale ≈ +1,1º.

Dato che l'Ara Pacis fu inaugurata nel 9 a.C. (Moretti 1947, 7), il planetario digitale Starry Night Pro ha calcolato che il vettore astro-orizzonte dell'apertura nord-est dell'Ara Pacis era originariamente orientato verso il Sole nascente (+11,0ºδ) sia il 21 aprile che il 27 agosto del 9 a.C.  Tuttavia, l'iconografia sul fregio << Tellus >> dell'esterno nord-est supporta l'interpretazione che solo l'alba del 21 aprile fosse significativa, perché ogni elemento scultoreo del fregio – giovane donna (Venere), anfora fluente (Acquario), coppia di pesci (Pesci), ariete (Ariete), toro (Toro), gemelli neonati (Gemelli) – rispecchia l'ascesa eliaca di Venere/Stella del Mattino in Ariete tra le cinque costellazioni dello zodiaco primaverile viste dall'altare sacrificale interno all'alba della Festa di Palilia (Parilia) (Pales, dea dei pastori), il 21 aprile 9 a.C.  In questo giorno si commemora la fondazione di Roma, il 21 aprile 1 ab urbe condita (AUC) nella cronologia di Marcus Terentius Varro, cioè la 93a iterazione nel periodo sinodico Terra-Venere di 8 anni dell'ascesa eliaca di Venere/Stella del Mattino nella costellazione dell'Ariete sul Dies Natalis Romae, 21 aprile 753 a.C.

A newly developed Atmospheric General Circulation Model (AGCM) at T62 spectral truncation with 28 terrain-following levels coupled to the Modular Ocean Model version 3.0 (MOM3.0) is evaluated for its simulation of El Niño and the Southern Oscillation (ENSO). It is also compared with an older version of the AGCM coupled to the same ocean model. A dozen features of ENSO are validated. These characteristics of ENSO highlight its influence on global climate at seasonal to interannual scales.The major improvements of the ENSO simulation from this new coupled climate model are the seasonal phase locking of the ENSO variability to a realistic annual cycle of the eastern equatorial Pacific Ocean, the duration of the ENSO events and its evolution that is comparable to the ocean data assimilation. The two apparent drawbacks of this new model are its relatively weak ENSO variability and the presence of erroneous split ITCZ.The improvement of the ENSO simulation in the new coupled model is attributed to realistic thermocline variability and wind stress simulation.

The magnitude and location of terrestrial carbon sources and sinks remains subject to large uncertainties. Estimates of terrestrial CO 2 fluxes from ground-based inventory measurements typically find less carbon uptake than inverse model calculations based on atmospheric CO 2 measurements, while a wide range of results have been obtained using models of different types. However, when full account is taken of the processes, pools, time scales and geographic areas being measured, the different approaches can be understood as complementary rather than inconsistent, and can provide insight as to the contribution of various processes to the terrestrial carbon budget. For example, quantitative differences between atmospheric inversion model estimates and forest inventory estimates in northern extratropical regions suggest that carbon fluxes to soils (often not accounted for in inventories), and into non-forest vegetation, may account for about half of the terrestrial uptake. A consensus of inventory and inverse methods indicates that, in the 1980s, northern extratropical land regions were a large net sink of carbon, and the tropics were approximately neutral (albeit with high uncertainty around the central estimate of zero net flux). The terrestrial flux in southern extratropical regions was small. Book-keeping model studies of the impacts of land-use change indicated a large source in the tropics and almost zero net flux for most northern extratropical regions; similar land use change impacts were also recently obtained using process-based models. The difference between book-keeping land-use change model studies and inversions or inventories was previously interpreted as a "missing" terrestrial carbon uptake. Land-use change studies do not account for environmental or many management effects (which are implicitly included in inventory and inversion methods). Process-based model studies have quantified the impacts of CO 2 fertilisation and climate change in addition to land use change, and found that these environmental effects are in the right order of magnitude to account for the "missing" terrestrial carbon uptake. Despite recent carbon losses due to fire and insect attack in Canada and Russia, the northern extratropical regions generally have been a net carbon sink, only partially due to land-use changes such as abandonment of agricultural land. In the tropics, inventory data and flux measurements in extant forests support the existence of an environmental or management sink that counterbalances the effect of deforestation. Woody encroachment in savannas may also be a significant (but as yet poorly quantified) cause of tropical carbon uptake.

This article reports on the inland re-intensification of tropical storm (TS) Erin (2007). In this research, the physical processes that resulted in the re-intensification of TS Erin over Oklahoma, USA, on 19 August 2007 was determined and a sensitivity study on microphysics, planetary boundary layer and convective parameterisation schemes was performed in the mesoscale modelling system, MM5. Also, we diagnosed and explained the remarkable difference between model behaviour of the original KainÁFritsch 1 (KF1) scheme and its revised counterpart (KF2). The numerical results showed only modest sensitivity to the selected microphysics schemes Á the relatively simple 'Simple Ice' and the advanced Reisner-Graupel. We found a relatively high sensitivity to the selected boundary layer parameterisation. Enhanced mixing in the medium range forecast (MRF) scheme leads to a relatively small convective available potential energy (CAPE), a deeper boundary layer and a lower dew point temperature, thus to a relatively stable environment. Therefore, MRF forecasts less precipitation (up to 150 mm) than the local mixing scheme, ETA. Model results appeared most sensitive to the selected convection schemes, that is, Grell, KF1 and KF2. With Grell and KF1, Erin intensifies and produces intense precipitation, but its structure remains close to a mesoscale convective system (MCS) or squall line rather than of the observed tropical cyclone. Both schemes also simulate the most intense precipitation too far south (100 km) compared to observations. On the contrary, KF2 underestimates precipitation, but the track of the convection, the precipitation and the pressure distribution are relatively close to radar and field observations. A sensitivity study reveals that the downdraft formulation is critical to modelling TS Erin's dynamics. Within tropical cyclogenesis, the mid-level relative humidity (RH) is generally very high, resulting in very small downdrafts. KF2 generates hardly any downdrafts due to its dependence on mid-level RH. However, KF1 and Grell generate much stronger downdrafts because they both relate the downdraft mass flux (DMF) to vertical wind shear. This larger DMF then completely alters TS Erin's dynamics. A modified version of the Grell scheme with KF2 RH-dependent downdraft formulation improved the simulation considerably, with better resemblance to observations on trajectory, radar reflectivity and system structure.

A B S T R A C T Different initial perturbation methods for the mesoscale ensemble prediction were compared by the Meteorological Research Institute (MRI) as a part of the intercomparison of mesoscale ensemble prediction systems (EPSs) of the World Weather Research Programme (WWRP) Beijing 2008 Olympics Research and Development Project (B08RDP). Five initial perturbation methods for mesoscale ensemble prediction were developed for B08RDP and compared at MRI: (1) a downscaling method of the Japan Meteorological Agency (JMA)'s operational one-week EPS (WEP), (2) a targeted global model singular vector (GSV) method, (3) a mesoscale model singular vector (MSV) method based on the adjoint model of the JMA non-hydrostatic model (NHM), (4) a mesoscale breeding growing mode (MBD) method based on the NHM forecast and (5) a local ensemble transform (LET) method based on the local ensemble transform Kalman filter (LETKF) using NHM. These perturbation methods were applied to the preliminary experiments of the B08RDP Tier-1 mesoscale ensemble prediction with a horizontal resolution of 15 km. To make the comparison easier, the same horizontal resolution (40 km) was employed for the three mesoscale model-based initial perturbation methods (MSV, MBD and LET).

This study examines eight microphysics schemes (Lin, WSM5, Eta, WSM6, Goddard, Thompson, WDM5, WDM6) in the Advanced Research Weather Research and Forecasting Model (WRF-ARW) for their reproduction of observed strong convection over the US Southern Great Plains (SGP) for three heavy precipitation events of 27Á31 May 2001. It also assesses how observational analysis nudging (OBNUD), threedimensional (3DVAR) and four-dimensional variational (4DVAR) data assimilation (DA) affect simulated cloud properties relative to simulations with no DA (CNTRL). Primary evaluation data were cloud radar reflectivity measurements by the millimetre cloud radar (MMCR) at the Central Facility (CF) of the SGP site of the ARM Climate Research Facility (ACRF). All WRF-ARW microphysics simulations reproduce the intensity and vertical structure of the first two major MMCR-observed storms, although the first simulated storm initiates a few hours earlier than observed. Of three organised convective events, the model best identifies the timing and vertical structure of the second storm more than 50 hours into the simulation. For this wellsimulated cloud structure, simulated reflectivities are close to the observed counterparts in the mid-and upper troposphere, and only overestimate observed cloud radar reflectivity in the lower troposphere by less than 10 dBZ. Based on relative measures of skill, no single microphysics scheme excels in all aspects, although the WDM schemes show much-improved frequency bias scores (FBSs) in the lower troposphere for a range of reflectivity thresholds. The WDM6 scheme has improved FBSs and high simulated-observed reflectivity correlations in the lower troposphere, likely due to its large production of liquid water immediately below the melting level. Of all the DA experiments, 3DVAR has the lowest mean errors (MEs) and root mean-squared errors (RMSEs), although both the 3DVAR and 4DVAR simulations reduced noticeably the MEs for seven of eight microphysics schemes relative to CNTRL. Lower-tropospheric u e and convective available potential energy (CAPE) also are closer to the observations for the 4DVAR than CNTRL simulations.

O objetivo deste texto é ressaltar a importância do tratamento do sofrimento psíquico em discentes pertencentes a populações indígenas em suas trajetórias acadêmicas na Universidade Federal de Goiás (UFG). Para tanto, foram realizadas análises a partir da experiência vivenciada por parte dos estudantes indígenas no curso de Educação Intercultural e nos demais cursos de graduação e pós-graduação da UFG. Na última década, tais contingentes populacionais têm acessado cada vez mais a academia, onde antes eram apenas excluídos. Desta forma, para que suas trajetórias acadêmicas, importantes para eles, suas comunidades, a universidade e o país, concluam-se com bem- estar e saúde, torna-se fundamental explorar todos os aspectos das políticas de permanência na universidade, como o sofrimento psíquico. Tendo em vista as abordagens presentes nos referenciais teóricos e metodológicos do grupo modernidade/colonialidade/decolonialidade, a hipótese presente em nosso estudo é de que há uma relação ...

Net ecosystem-atmosphere exchange of CO 2 (NEE) was measured in two boreal bogs during the snow-free periods of 1998, 1999 and 2000. The two sites were located in European Russia (Fyodorovskoye), and in central Siberia (Zotino). Climate at both sites was generally continental but with more extreme summer-winter gradients in temperature at the more eastern site Zotino. The snow-free period in Fyodorovskoye exceeded the snow-free period at Zotino by several weeks. Marked seasonal and interannual differences in NEE were observed at both locations, with contrasting rates and patterns. Amongst the most important contrasts were: (1) Ecosystem respiration at a reference soil temperature was higher at Fyodorovskoye than at Zotino. (2) The diurnal amplitude of summer NEE was larger at Fyodorovskoye than at Zotino. (3) There was a modest tendency for maximum 24 h NEE during average rainfall years to be more negative at Zotino (−0.17 versus −0.15 mol m −2 d −1 ), suggesting a higher productivity during the summer months. (4) Cumulative net uptake of CO 2 during the snow-free period was strongly related to climatic differences between years. In Zotino the interannual variability in climate, and also in the CO 2 balance during the snow-free period, was small. However, at Fyodorovskoye the bog was a significant carbon sink in one season and a substantial source for CO 2 -C in the next, which was below-average dry. Total snow-free uptake and annual estimates of net CO 2 -C uptake are discussed, including associated uncertainties.

A B S T R A C T This paper proposes a simple approach to estimating multiplicative model parameters using the ensemble square root filter. The basic idea, following previous studies, is to augment the state vector by the model parameters. While some success with this approach has been reported if the model parameters enter as additive terms in the tendency equations, this approach is problematic if the model parameters are multiplied by the state variables. The reason for this difficulty is that multiplicative parameters change the dynamical properties of the model, and in particular can cause the model to become dynamically unstable. This paper shows that model instability can be avoided if the usual persistence model for parameter update is replaced by a temporally smoothed version of the update model. In addition, the augmentation approach can be interpreted as two simultaneously decoupled ensemble Kalman filters for the model state and the parameter state, respectively. Implementation of the parameter estimation does not require changing the data assimilation algorithm-it just has to be supplemented by a parameter estimation step that is similar to the state estimation step. Covariance localization is found to be necessary not only for the model state, but also for augmented model parameters, if they are spatially dependent. The new formulation is illustrated with the Lorenz-96 model and shown to be capable of estimating additive and multiplicative model parameters, as well as the state, under relatively challenging conditions (e.g. using 20 observations to estimate 120 unknown variables).

A B S T R A C T The multi-model ensemble for seasonal to interannual prediction developed in the European Union project DEMETER has been used to quantify the predictability of monthly average maximum temperature that could be achieved operationally over the Iberian Peninsula. Statistical downscaling based on canonical correlation analysis is applied to increase the spatial resolution available from the global models. The downscaling is based on empirical connections between the North Atlantic sea level pressure and monthly average maximum temperature over the Iberian Peninsula.

The relative entropy is compared with the previously used Shannon entropy difference as a measure of the amount of information extracted from observations by an optimal analysis in terms of the changes in the probability density function (pdf) produced by the analysis with respect to the background pdf. It is shown that the relative entropy measures both the signal and dispersion parts of the information content from observations, while the Shannon entropy difference measures only the dispersion part. When the pdfs are Gaussian or transformed to Gaussian, the signal part of the information content is given by a weighted inner-product of the analysis increment vector and the dispersion part is given by a non-negative definite function of the analysis and background covariance matrices. When the observation space is transformed based on the singular value decomposition of the scaled observation operator, the information content becomes separable between components associated with different singular values. Densely distributed observations can be then compressed with minimum information loss by truncating the components associate with the smallest singular values. The differences between the relative entropy and Shannon entropy difference in measuring information content and information loss are analysed in details and illustrated by examples.

Background.  The Ara Pacis Augustae (Altar of the Augustan Peace, Rome, Italy, 13-9 BC) is examined as a shrine of light consistent with the astro-orientation principles of Roman architect Vitruvius (c.15 BC, IV:v:1, IV:ix:i).  Italian archaeologists excavated (1937-8) the altar some 10 meters under the Via in Lucina, 16 and reassembled it (rotated 75º counter-clockwise from the original) 455 meters NW along the Tiber River (Moretti 1947, 6; Andersen 2003, 5).  While "la bella figura" of its polychrome marble sculpture (Kleiner 1992, 90-99; Foresta 2011) is displayed at the Museo dell’Ara Pacis, until now, the secret of its astro-orientation has remained encoded on a paper site plan.

Data.  Computer programs “Stonehenge” (Hawkins 1983, 328-330) and “Starry Night Pro Plus 6” calculated the  horizon declination (+11.3º decl.) of the altar’s original North-East facing with the following input data from the site plan by Guglielmo Gatti c.1938 (Stampini 1970, Fig. 2, p. 36) and Google Earth: True Azimuth ≈ 75º; Latitude/Longitude = 41° 54’ 10.47” N/12° 28’ 44.60” E; Elevation ≈ 10 meters ASL; and Horizon Altitude ≈ +1.1º.  The Ara Pacis Augustae was dedicated in 9 BC for an annual ceremony by Vestal Virgins  (Res Gestae Divi Augusti, 12.2).

Results.  The axis of the Ara Pacis Augustae twin enclosure entrances was originally oriented SW-NE to the first gleam of the rising Sun (+11.0º decl.) at dawn on both 21 April and 27 August 9 BC.

Analysis & Conclusion.  The iconography of the Ara Pacis supports the interpretation that the April 21st sunrise was the date and time of the annual ceremony, e.g., the seated woman (Galinsky 1992), bull and sheep frieze above the tetra-gammadion Μαίανδρος correspond to the heliacal rise of the planet Venus as Morning Star with zodiac constellations Aries and Taurus on the horizon for the festival of Par ilia (Pales, goddess of shepherds) on 21 April 9 BC, i.e., the anniversary of the founding of Rome in 1 a.u.c. (753 BC) according to the Roman historian Marcus Terentius Varro.  Moreover, Hannah & Magli 2011 report another solar-calendric orientation for April 21st of politico-religious importance, i.e., the Pantheon’s (Hadrian, c.125 AD) oculus-to-entrance solar-noon/meridian transit alignment.  Therefore, a virtual digital 3D animation modeling Roman astro-architectural principles linking the Pax Augusta and Dies Natalis Urbis Romae deserves  exhibition at the Museo dell’Ara Pacis, Rome.

A mathematical model is employed for analysing the structure of the homogeneous ocean surface layer. The model is verified against laboratory measurements of the fully developed channel flow and the wind-induced channel flow. Turbulence models of different complexities are used and discussed. An extension of the k-6 turbulence model to rotating flows is derived and tested. The study indicates that a suitably chosen constant eddy viscosity is adequate for predicting the velocity and shear stress distributions in the Ekman layer. For transport of different chemical and biological species it is, however, necessary to know the detailed transport properties of the layer. Non-dimensional vertical distributions of different turbulence quantities, characterizing the Ekman layer, are therefore predicted and analysed. Rotational effects in the turbulence model are found to somewhat change the shear stress distribution in the deeper parts of the boundary layer.

This overview summarizes the objectives of the Aerosol Characterization Experiments (ACEs) of the International Global Atmospheric Chemistry (IGAC) project and the research strategy implemented in the second of this series of experiments (ACE-2). ACE-2 took place from 16 June to 24 July 1997, over the sub-tropical North-East Atlantic. It provided an opportunity to study the properties, processes and effects of contrasting aerosol types in this region, including background marine and anthropogenic pollution aerosol in the marine boundary layer (MBL), and background aerosol and mineral dust in the overlaying free troposphere (FT). The major achievements of ACE-2 include: (a) identification of entrainment, in-cloud scavenging and coagulation as the major processes transforming a pollution aerosol transported within the MBL; (b) the first documentation of the indirect radiative effect of aerosols at the scale of a cloud ensemble in continental pollution outflow; (c) observation of a wide range in the contribution of organic material to the sub-micron aerosol mass, with possibly the highest contribution in the free tropospheric; (d) improved understanding of the role of condensing HCl, HNO 3 and NH 3 as a growth mechanism of sub-micron aerosols in polluted air masses advecting over the ocean. A close connection was observed between meteorological factors (such as horizontal and vertical wind speed, boundary layer development, entrainment, humidity fields) and aerosol and cloud characteristics. In the ACE-2 region, these meteorological factors, rather than aerosol microphysics and chemistry, often dominated the shaping of the aerosol size distribution and/or their effect on radiation and clouds. The ACE-2 data presently analyzed provide a qualitative, and in many cases a quantitative understanding of the complex gas/aerosol/cloud system in the sub-tropical marine environment. This will guide future model development. Some major data sets are still to be analyzed.

I n a parcel of moist air in contact with a lake surface, water molecules, both H,O and HTO, are transferred both ways between the gaseous and liquid phases. The net transfers of H,O and of HTO are in the direction of decreasing chemical potential of each species. These directions may be opposite. We introduce the following notations: E H~O~ Q9 P w e , e w 1 Y a b k EHT0 Upward net flux of H,O, HTO in g cm-a sec -1 Specific humidity (g HIO/kg air) in free air, at lake surface (saturation) Tritium concentration, in TU, of free air vapor, of lake surface water Time Fractionation factor (pHTO/pHIO) at saturation, also (evaWr/Olipuid) a t equilibrium Transforms specific humidity to height of precipitable water column (g cm-8) in layer affected (sampled) Transforms TU to g HTO/g H,O Eddy diffusion coefficient of vapor in air, same for both species of water According to approaches proposed by Bolin (1958), Machta (1969), and others, we can write for the fluxes at the airflake interface Ell,, -a*dqldt -a -k (9, -n) (1) EHTo =a.b.d(qO)/dt-a.b.k (qw€Jwy -qO) (2) where we aasume H,O and HTO to have same Contribution no. 1221 from the Institute of Marine end Atmospheric Sciences. University of Miami. Tellus XXII (1970), 4

Globally forced model simulations with an atmospheric general circulation model of intermediate complexity reveal surface air temperature (SAT) and sea level pressure (SLP) variations at multidecadal time scales. In order to separate the influence of individual ocean basins on the North Atlantic multidecadal variability, we force our model with observed SST data for the period 1856-2000 for Atlantic and Pacific Oceans, separately, while outside the atmosphere is coupled with the ocean via a mixed layer slab model. The experiments indicate the Atlantic Ocean as a principal driver of North Atlantic multidecadal variability, with SAT and SLP highly in phase in the North Atlantic at about 60-70 years time scale. The Pacific impact is associated to longer period variations in the SLP field over the North Atlantic. We suggest that two distinct physical modes of multidecadal climate variability exist, one of about 70 years possibly linked with the Atlantic thermohaline circulation, the other linked with the Pacific Ocean and connected to the Atlantic Ocean via Pacific -North America teleconnections. The latter has a time scale of about 80-100 years.

O objetivo deste artigo é expor as metodologias e a produção de dados utilizados em duas pesquisas de Mestrado desenvolvidas com os povos indígenas do estado de Rondônia. Assim, propomos neste texto abordar, bem como problematizar, as fontes metodológicas, as articulações realizadas no contexto teórico metodológico das dissertações de mestrado desenvolvidas com povos indígenas de Rondônia. A questão norteadora deste excerto vincula-se às concepções metodológicas na produção de dados e à “descolonização de nós mesmos” no sentido de que ambos os autores sofreram ressignificações no contexto da pesquisa com os povos indígenas de Rondônia. Como possibilidades conclusórias, problematizamos a relação de experiência e vivência com os sujeitos pesquisados no contexto da produção de dados de uma pesquisa de mestrado. A relação com o outro: estar com outro, ouvir, negociar, possibilita ao sujeito pesquisador (a) novas fontes metodológicas e novos olhares sobre o pesquisar.

We examine the application of ensemble Kalman filter algorithms to the smoothing problem in high-dimensional geophysical prediction systems. The goal of smoothing is to make optimal estimates of the geophysical system state making best use of observations taken before, at, and after the analysis time. We begin by reviewing the underlying probabilistic theory, along with a discussion how to implement a smoother using an ensemble Kalman filter algorithm. The novel contribution of this paper is the investigation of various key issues regarding the application of ensemble Kalman filters to smoothing using a series of Observing System Simulation Experiments in both a Lorenz 1996 model and an Atmospheric General Circulation Model. The results demonstrate the impacts of non-linearities, ensemble size, observational network configuration and covariance localization. The Atmospheric General Circulation model results demonstrate that the ensemble Kalman smoother (EnKS) can be successfully applied to high-dimensional estimation problems and that covariance localization plays a critical role in its success. The results of this paper provide a foundation of understanding which will be useful in future applications of EnKS algorithms.

Este estudo aborda o processo de resistência dos guarani das missões dos Sete Povos entre os anos de 1750 e 1756 contra o Tratado de Madri (1750), destacando como a resistência indígena se configura enquanto um processo de reconhecimento de direitos e de diferenças sociais, econômicas e culturais em relação ao modelo colonial. Desse modo, a resistência dos guarani-missioneiros ganha contornos de autodeterminação de sujeitos subalternizados no aporte teórico decolonial. Nesse sentido, este artigo aborda, brevemente, o processo de transformação cultural e constituição da identidade étnica guarani-missioneiro, e como a luta contra as prerrogativas do Tratado de Madri foi uma busca por manutenção da unidade étnica constituída no cosmos missioneiro. A partir disso, aborda-se a consciência dos guarani-missioneiros de sua importância nos meandros geopolíticos dos séculos XVII e XVIII na região platina e, de igual modo, problematiza-se a situação de negociações entre os indígenas e outros atores que compunham o cenário geopolítico da região, afinal, quando obrigados a saírem de suas terras, os guarani-missioneiros resistiram, advertindo a elite colonial dos seus feitos em prol da Espanha. O objetivo central é, pois, apresentar o protagonismo indígena no processo de luta pela terra e por seus direitos, através de uma perspectiva epistemológica que transcenda as velhas análises eurocêntricas e etnocêntricas sobre o passado missioneiro: em termos historiográficos, utilizaremos estudos comprometidos com um olhar crítico das fontes, tais

Physico-chemical hydrodynamics of bubble-breaking and surface chemistry together will explain many of the anomalous ion-ratios reported for the marine component of atmospheric aerosols and precipitation.The “enrichment” of phosphate in bubble-produced aerosol from a solution containing radioactive P-32 and Na-22 is defined asE = (P-32/Na-22) aerosol/(P-32/Na-22) solution − 1and is positive for all solutions studied. Phosphate is always present in excess in drops from breaking bubbles. For jet drops, E lies between 0.01 and 10; for drops from film caps which have drained and lost nearly all of their bulk solution, E may rise as high as 1000. Phosphate is preferred to chloride as a counter-ion below positively-charged surfactants, and also seems to be bound to peptide-like uncharged materials.The mechanism is not specific for phosphate, but can be invoked to explain the enrichment of any constituent of marine aerosol whose absolute ionic potential is greater than Na+ or Cl−.

ABSTRACT Water cooling in the entrance of the Baltic Sea is analyzed using measured and numerically simulated data. The measurements cover two cooling periods from the prelude of the severe sea ice winters 1984/85 and 1985/86, during which the surface water was cooled from 10°C to freezing. The calculations are based upon a mathematical model which divides the entrance of the Baltic Sea into four sub-basins: the Kattegat, the Belt Sea, öresund and the Arkona Basin. In each sub-basin, the conservation equations for momentum, heat and salt in the vertical dimension are solved with vertical mean velocities based upon parameterized in- and outflows. The turbulent exchange coefficients are calculated using a two-equation model of turbulence.The measured data demonstrate the importance of considering the exchange through the entrance of the Baltic Sea when modelling autumn cooling. The mathematical model describes the exchange and the general development of the cooling in a satisfactory way.

Deep-water exchange and mixing properties in the Baltic Proper were analysed on the basis of temperature and salinity data measured during the period 1970 90. The data were analysed applying basic model concepts as the conservation principles, the two-layer approach and the geostrophic flow assumption. The renewal of the deep water in the Baltic Proper consists of inflow from upstream basins. The inflowing dense water is diluted by surface water and on a 20-year average increased by a factor of 4, when entering from the Kattegat into the Landsort Deep. Three main mixing zones were localized. Firstly, the Belt Sea and the Sound, where the deep-water inflow increases by 79%; secondly, the Arkona Basin, where vertical mixing causes the increase of deep current volume flow by an average of 53%; and thirdly, in the Stolpe Channel, where the turbulent entrainment adds an average of 28% to the deep current. Applying the geostrophic flow model on salinity data, time series of deep current flow rates were calculated. The model was calibrated by 20-year mean flows calculated from conservation principles. The effective sill depths were introduced as calibration coefficients. It was found that the geostrophic flow model described deep-layer flows in the Bornholm Channel well, but the flow rate was underestimated in the Stolpe Channel and overestimated in the Fårö Channel. In the Stolpe Channel and in the Fårö Channel, the deep-layer flow showed seasonal variations with rapid increase during the autumn and winter seasons, respectively.

Precipitation and evaporation over the Baltic Sea are calculated for a one-year period from September 1998 to August 1999 by four different tools, the two atmospheric regional models HIRLAM and REMO, the oceanographic model PROBE-Baltic in combination with the SMHI (1 × 1) • database and Interpolated Fields, based essentially on ship measurements. The investigated period is slightly warmer and wetter than the climatological mean. Correlation coefficients of the differently calculated latent heat fluxes vary between 0.81 (HIRLAM and REMO) and 0.56 (SMHI/PROBE-Baltic and Interpolated Fields), while the correlation coefficients between model fluxes and measured fluxes range from 0.61 and 0.78. Deviations of simulated and interpolated monthly precipitation over the Baltic Sea are less than ±5 mm in the southern Baltic and up to 20 mm near the Finnish coast for the one-year period. The methods simulate the annual cycle of precipitation and evaporation of the Baltic Proper in a similar manner with a broad maximum of net precipitation in spring and early summer and a minimum in late summer. The annual averages of net precipitation of the Baltic Proper range from 57 mm (REMO) to 262 mm (HIRLAM) and for the Baltic Sea from 96 mm (SMHI/PROBE-Baltic) to 209 mm (HIRLAM). This range is considered to give the uncertainty of present-day determination of the net precipitation over the Baltic Sea.

The variations in tropopause height with sunspot activity for 11 Indian stations have been studied for the period 1960 to 1972. The annual mean tropopause heights were plotted against Zurich sunspot numbers. The plots show clear latitudinal dependence in height variations. We calculated the correlation coefficients between tropopause height and sunspot numbers for lags varying from 0 to 5 years. The correlation coefficients for lag = 0 and lag = 3 exhibit entirely different latitudinal dependence. The largest negative correlatidn for mid-latitudes and an insignificant correlation for equatorial regions is found with lag = 0; whereas, for a lag of 3 years, the largest negative correlation is seen in the equatorial region with insignificant correlation for mid latitudes. This study shows that in low latitudes both the particle and electromagnetic part of the solar radiation cause changes in atmospheric circulation. Differences in sign of correlation coefficients between Indian and American regions suggest strong longitudinal dependence of sdar-meteorological relationships' Tellus 3 1 (l979),6 0040-2826/79/0605 15-06%02.50/0 0 1979 Munksgaard. Copenhagen

Este trabalho apresenta a forma de manejo da fl oresta naformacao de “rocados” pela populacao indigena Deni, desde a escolhada area ate a confeccao da farinha. Usou-se como referencia o manejoem sete comunidades ao longo dos rios Xerua e Cuniua, no estado doAmazonas, Brasil. Ao manejarem a fl oresta para a formacao de areascultivadas, estas sao deixadas em “pousios” apos dois anos de uso eenriquecidas com outras especies domesticadas, transformam-se emsistemas agrofl orestais onde se tornam locais permanentes de coletade frutos e de cacas que ali buscam abrigo e alimento. A farinha demandioca e o principal produto originado do rocado e um importanteinstrumento de troca com outros produtos e artefatos nao produzidospela populacao Deni.Palavras-chave: sistema agrofl orestal; pousio; Deni.

O artigo tem como objetivo refletir e problematizar as conexões e diálogos de professores indígenas e não indígenas, participantes de uma formação continuada em rede social. Os dados apresentados são resultados parciais de uma pesquisa iniciada em 2011[1]. Insere-se no Grupo de Pesquisa e Estudos em Tecnologia Educacional e Educação a Distância (GETED)[2]. Optamos por uma abordagem de pesquisa qualitativa sob a forma de etnografia virtual. Como procedimento metodológico, utilizaram-se depoimentos das interações entre os sujeitos participantes da formação continuada virtual na rede social Facebook. Na tessitura deste artigo, buscamos organizar nossos tateios e experiências em três momentos. Primeiramente, trazemos à reflexão fundamentos teóricos sobre a formação continuada intercultural e suas contribuições para a educação. No segundo momento, mergulhando nas vozes dos professores parceiros da pesquisa, tecemos as conexões e diálogos no Facebook, apresentando os seus anseios, problem...

A B S T R A C T Convective vortices are common features of atmospheres that absorb lower-entropy-energy at higher temperatures than they reject higher-entropy-energy to space. These vortices range from small to large-scale and play an important role in the vertical transport of heat, momentum, and tracer species. Thus, the development of theoretical models for convective vortices is important to our understanding of some of the basic features of planetary atmospheres.

O termo bem viver se tornou um conceito nativo dos ameríndios para mostrar a sua cosmovisão diferenciada do Ocidente. Aqui o autor acrescenta, a partir de sua etnografia com os Wapichana, mais uma categoria nativa, kaimen. Os Wapichana que vivem em Roraima (Brasil) e na Guyana encontraram na palavra kaimen um modo de expressar sua cosmologia. As relações sociocosmológicas Wapichana passam pelo trabalho, comida, desenhos em altos-relevos esculpidos nas rochas, rituais e falas nativas.  Nesse contexto, a roça de mandioca, associada aos seus usos e costumes tradicionais, é uma metáfora para lidar com as fronteiras criadas entre os dois países e que dividiram os Wapichana. Por isso, afirmam que ultrapassar as fronteiras impostas pelos países é kaimen.

The dependence of the performance of mesoscale-α and mesoscale-β models on model resolution and parameterisation of sub-grid-scale land-use effects is investigated for a meteorological situation that is strongly influenced by local effects. Two mesoscale models of different horizontal resolution and model physics are applied to the same meteorological situation, and the results are compared with observations. Sensitivity studies are performed to estimate the effect of resolution (4 km or 5 km versus 18 km), parameterisation of sub-grid-scale land-use effects and initial state on the results of both models. Results show that the accuracy improves with resolution when simple parameterisations of sub-grid-scale land-use effects are applied. The inclusion of sub-grid-scale land-use effects with application of a flux aggregation method provides the best solution, which is nearly independent of the resolutions used. The use of parameter averaging to account for sub-grid-scale land-use effects was worse than just using one (main) land-use per grid cell. Initial conditions were also found to have a significant impact on the results.

A B S T R A C T The trajectories of 61 profiling Argo floats deployed at mid-depth in the Nordic Seas-the Greenland, Lofoten and Norwegian Basins and the Iceland Plateau-between 2001 and 2009 are analysed to determine the pattern, strength and variability of the regional circulation. The mid-depth circulation is strongly coupled with the structure of the bottom topography of the four major basins and of the Nordic Seas as a whole. It is cyclonic, both on the large-scale and on the basin scale, with weak flow (<1 cm s −1 ) in the interior of the basins and somewhat stronger flow (up to 5 cm s −1 ) at their rims. Only few floats moved from one basin to another, indicating that the internal recirculation within the basins is by far dominating the larger-scale exchanges. The seasonal variability of the mid-depth flow ranges from less than 1 cm s −1 over the Iceland Plateau to more than 4 cm s −1 in the Greenland Basin. These velocities translate into internal gyre transports of up to 15 ± 10 × 10 6 m 3 s −1 , several times the overall exchange between the Nordic Seas and the subpolar North Atlantic. The seasonal variability of the Greenland Basin and the Norwegian Basin can be adequately modelled using the barotropic vorticity equation, with the wind and bottom friction as the only forcing mechanisms. For the Lofoten Basin and the Iceland Plateau less than 50% of the variance can be explained by the wind.

A B S T R A C T Gravity waves over a small nunatak in Dronning Maud Land, Antarctica, were simulated applying the mesoscale model Weather Research and Forecasting (WRF). Most model experiments were made using three nested domains with 0.9 km horizontal resolution in the finest grid. The model results were validated against observations from a vertically pointing 54.5 MHz VHF radar, which provided profiles of the vertical and horizontal wind components over the nunatak. The WRF model generated gravity waves in the periods when these were observed. The modelled wave characteristics were qualitatively similar to the observed ones, although quantitative differences existed. The gravity wave had a typical vertical wave length of 3-4 km, and a maximum amplitude of 1 m s −1 in the vertical velocity field. The amplitude was largest at altitude of 2.0-3.5 km. The wave was strongest during nighttime, when the surface sensible heat flux was downwards. The evolution of vertical profiles of the observed rms fluctuation of vertical wind velocity and the modelled bulk Richardson number resembled each other. Gravity waves may affect the safety of aircraft landing and take-off on the lee side of the nunatak.

Hemisphere, and is adjacent to the continent's most intense katabatic wind regime. However, the physical mechanisms responsible for cyclogenesis are not known. A manual analysis of cyclogenesis for the 2003-2005 period using output from the Antarctic Mesoscale Prediction System (AMPS) identifies two primary patterns of cyclogenesis near the Adélie Land coast. For "secondary development" cyclones, enhanced low-level cyclonic vorticity and baroclinicity result from the combination of an existing synoptic-scale cyclone to the west, coastal barrier winds and katabatic winds. "Lee cyclogenesis" occurs near 152 • E on the cyclonic-shear side of the Adélie Land katabatic jet, where a low-level warm potential temperature anomaly sets up a lee trough that becomes mobile with the arrival of upper-level synopticscale forcing. The representation of both "secondary development" and "lee cyclogenesis" cyclones in an automated cyclone-tracking scheme is explored, where it is found that the automated scheme overestimates cyclogenesis for this region. The location of the Antarctic coastal cyclogenesis maximum near Adélie Land is due to the unique juxtaposition of the extraordinary katabatic wind regime and dissipating synoptic-scale cyclones to the west.

A numerical technique is presented for calculating where, on average, tracer particles at a particular place in a turbulent medium were created, and where they will be destroyed. This technique requires knowledge of creation, destruction, and transport rates, and gives as results probability distributions for creation and destruction. The technique is demonstrated on a model of stratospheric ozone, and a rough quantification is made of the statement that high latitude, low altitude ozone tends to be created in low latitude, high altitude regions.

En este texto nos proponemos analizar las transformaciones asociadas al liderazgo que atraviesan las mujeres guaraníes de la provincia de Misiones. La hipótesis central de esta exploración es que el rol de las mujeres guaraníes dentro de la comunidad se encuentra en un proceso particular de transformación, que aleja a ciertas mujeres del lugar históricamente más tradicional, ligado al ámbito doméstico y las relaciones con el propio grupo. Este rol se ve interpelado, tanto por los cambios dentro de los núcleos de la comunidad, así como por las nuevas subjetividades que emergen. Consideramos que en la cotidianidad as mujeres guaraníes se van posicionando en nuevos espacios y desarrollando habilidades específicas de los mismos que las diferencian, muchas de las cuales están potenciadas por la cotidianidad con la sociedad envolvente. Analizaremos los impactos de cacicas, auxiliares bilingües, agentes sanitarios y artesanas, y sus relaciones con el Estado, las ONG´s y la propia comunidad...

A new non-linear model of mixing and convection based upon a modelling by two buoyant interacting fluids is applied to the deepening of the wind-mixed layer. In view of simple algebra, the model is one-dimensional, frictionless, and neglects the turbulence production by the mean-flow shear in the thermocline. The potential-energy increase required for deepening is thus supplied by the turbulence input at the surface (turbulent erosion model). A non-similar analytical solution is found in the case of a well-mixed layer bounded below by a sharp thermocline, treated as a boundary layer. This solution is valid if the frictional Richardson number, Ri, defined as the ratio of the total mixed-layer buoyancy to the friction-velocity squared, is much greater than unity. The model predicts an entrainment rate proportional to Ri-', and a ratio of thermocline thickness to mixed-layer depth of the order of Ri-3'4. The thermocline shallows as h-1'2, as the mixed-layer depth, h, increases with time. The vertical structure throughout the mixed layer and thermocline is given by the solution, and vertical profiles of mean values and vertical fluxes are plotted. These profiles are comparable to those obtained by turbulence-closure numerical models.

The local pressure changes associated with the twice-annual contraction/intensification and expansion/weakening of the circumpolar trough of low pressure around Antarctica, termed the semiannual oscillation (SAO), was the dominant signal in the annual cycle at mid and high southern latitudes before 1979. The mechanism, as shown by Van Loon , arises from different response to the surface heat budget over the polar continent and the midlatitude ocean. It has subsequently been shown that in most years since 1979 the SAO has weakened considerably. Evidence is presented here from surface temperature data, 500 mb temperatures from a station pair and zonal mean 500 mb temperatures from the NCAR/NCEP reanalyses to show that a warming trend since 1979 has not been evenly distributed through the year at each latitude. Thus an anomalous change in the temperature gradient between 50°S and 65°S, with peaks in roughly May and November, has modulated the mechanism that produces the SAO, with its peaks in March and September. Consequently, the magnitude of the SAO has decreased in the more recent period.

The lunar semidiurnal term L,(p) has been investigated in detail on both a local and planetary basis and was found to be sensitive to the local diffusive character of the lowest layers of the atmosphere. Accordingly it is possible to explain the solar modulation of the M 2 pressure tide represented by the lunisolar diurnal term L , ( p ) and the seasonal behaviour of L , ( p ) as well as the variation of the phase angle A, with altitude.